PARTULA NODOSA. 89 
Punaruu Valley—sometimes called Punaauia, from the district in which it is 
so conspicuous a feature—is one of the few primary valleys in order of size (see 
plates 12 and 19). Its mouth is wide, and it remains relatively open in its inland 
extension. About 8 miles from the coast its floor rises more rapidly to a so-called 
“plateau,” beyond which the valley opens out into the crater-like basin of its 
commencement or “head.” Sharp-cut boundaries with precipitous walls separate 
this part from the beginnings of Fautaua and Temarua Valleys and from the great 
central basin of Papenoo. The land-mass between Punaruu and Fautaua is cut on 
its western slope by Taapuna Valley, one of the second order in size, and by several 
shallow but long gullies that prove to be unfavorable habitations for Partule. The 
greater mountain mass lying south of Punaruu, between it and Temarua, is divided 
by Orofere Valley, an element of the second order. Between the latter and the 
former the massif is cut by two valleys of the third order, Aoua and Papehue (see 
plate 15b), and by a few deep but short and narrow gorges, such as Atehi and 
Maruapoo. The above-mentioned geographical and topographical details must be 
taken into full account in dealing with the relationships of the various colonies of 
P. nodosa found in the valleys of this quadrant of the island. 
The material of the present investigation comprises 1,922 adults and 484 partly 
grown individuals; the former amount to 7.98 per cent of the mature population 
of the entire island, and to 42.78 per cent of the 4,492 adults obtained in the seven 
valleys where nodosa occurs. The adolescents of this species amount to 47.5 per 
cent of the number taken in the same range. ‘The absolute and relative members of 
nodosa in the several valleys are given in table 37, together with the numbers of 
dextral and sinistral individuals in each locality. 
TaBLe 37.—Partula nodosa. Frequency and distribution. 
No. of | Percentage) Dextral. Sinistral. 
Valley. adult of adult Variety. 
nodosa. |population.| No. (Per cent.| No. /Per cent. 
Taapuna...... 313 56.80 306 97.7 7 De, Vomrposite 
Runaruueeneiee 186 24.60 186 Sys 0 Nee all ; 
Maruapoo..... 795 84.12 28 3.5 767 96.4 | leva. 
ANtehitiey tense cree 4 0.89 4 Soyo 0 Lnstloge exigud. 
Papehue....... 210 53.57 210 0 50 
ANAS sooodogs 396 34.98 396 0 intermedia. 
Orofere........ 18 6.77 18 Rac 0 in fens 
142.79 | 
UGA o000 1,922 { 237 30 \1,148 774 
1Actual. 2A verage. 
Garrett’s circumstantial account of his observations on nodosa is sufficiently 
important to be quoted at length. He says: 
“This beautiful arboreal species is restricted to a limited area about two miles up 
Punaauia Valley on the west coast of Tahiti. I first discovered the location in 1861, and 
gathered about three hundred examples. On a subsequent visit, nine years later, I secured 
over eight hundred specimens. It is entirely confined to the south side of the stream which 
flows through the valley, and circumscribed in a narrow area three-quarters of a mile in 
length. When Mr. Pease described his trilineata he gave the correct locality; but, in his 
